Interdiffusion and related atomic mobilities in fcc Cu-Fe-Co alloys

Diffusion couples for fcc Cu-Fe-Co ternary system are prepared, all of which are annealed at 1573 K for 50 h. Interdiffusion coefficients are evaluated at the intersection points of two independent diffusion paths sharing a common composition. Such main and cross interdiffusion coefficients are then used to inversely retrieve atomic mobilities of Cu, Fe and Co in fcc Cu-Fe-Co alloys, with the aid of available thermodynamic description. Further validation concerning the quality of atomic mobilities is conducted with computational simulations for diffusion couples, the results of which are compared with experimental data. This work contributes to the establishment of a general Co-based kinetic database for computational design of superalloys.